What is the hardest natural substance on Earth?
Quiz Options
- Diamond
- Silver
- Platinum
- Ruby
Explanation
Diamond is the hardest substance found on earth in so many natural forms, and it is an allotrope of carbon. The hardness of diamond is the highest level of Mohs hardness - grade 10. Its microhardness is 10000kg/mm2, which is 1,000 times higher than quartz and 150 times higher than corundum.